1. Technical Field
The present invention relates to improvements in network design and in particular to improved methods and systems for bandwidth allocation for multimedia services under aggregate traffic conditions. Still more particularly, the present invention relates to a method and system for bandwidth allocation for multimedia services within a shared transmission medium in a manner which maximizes long-run average revenue.
2. Description of the Related Art
No where has the explosion of modern technology been more evident than in the field of communication. The number and type of communication services has been rapidly expanding, including so-called "multimedia" services such as video teleconferencing, video/movies on demand and the like.
The intermixing of these multimedia services with traditional data and voice communications within a shared transmission medium has presented various design problems. For example, consider a system which receives packetized telecommunication traffic from n multimedia services which are queued either in one central queue or in multiple distributed queues wherein one queue is associated with each service. Thus, if more than n subscribers to the services are utilizing the network at any given time, the received packets which are not processed by the system are queued. During heavy use periods, as the number of users increase, and these queues become quite large, certain packets may be discarded based upon a priority scheme and delay will increase and quality of service will suffer.
In the past, attempts at statistically modeling aggregate traffic which originates from homogenous services with similar traffic types and similar characteristics have been proposed. For example, the Poisson Process is widely utilized to model aggregate traffic from voice sources. Similarly, the discreet Auto Regressive Process has been utilized to model aggregate traffic from video-teleconferencing sources. A Markov Modulated Poisson Process is often utilized to model aggregate traffic from data sources. These techniques typically require complex mathematical expressions which are not explicit and which require time-consuming numerical methods to solve.
Those skilled in the art will appreciate that an accurate model of aggregate traffic within a network may be utilized to partition system capacity among multiple services. In the prior art, networks typically follow either the so-called "complete sharing" approach or the "complete partitioning" approach. In the complete sharing approach, each of the services within the system share system bandwidth on a first-come first-served basis. This approach is simple and utilizes system bandwidth efficiently; however, it may not maximize system revenue in a manner which is desired, in view of the extensive expense undertaken in the establishment of such networks. In the complete partitioning approach, each system has its own bandwidth and no two services share the same bandwidth. This approach can be utilized to maximize system revenue, for example, by assigning more bandwidth to expensive services than is assigned to lower priced services. However, the complete partitioning approach is not very flexible in that new services which are added to the network require a recalculation of the assigned bandwidth. Additionally, complete partitioning will sometimes waste system bandwidth because services can not share available bandwidth within an another partition within the system bandwidth.
It should thus be apparent to those skilled in the art that a method and system for efficient allocation of bandwidth for multimedia services under aggregate traffic conditions would result in a network in which the operators' return for operation of the network could be enhanced over the long term.